UGC NET Computer Science Software Engineering Previous Year Questions (PYQs) – Page 7 of 11

Increasing coupling (lower → higher):

• Stamp coupling (B): modules share a composite data structure but use only parts of it.

• Control coupling (C): one module controls another via flags/controls.

• External coupling (D): modules depend on externally imposed formats/protocols/devices.

• Common coupling (A): modules share global data.

• Content coupling (E): one module relies on or modifies another’s internal logic (worst).

Beta testing is performed after alpha testing.
In beta testing, software is given to selected real users or potential customers.
They test the software in their own real environment, not at the developer's location.
So, beta testing is performed by potential customers at their own locations.

MVC stands for Model View Controller.
In MVC, $V$ means View.
View is responsible for displaying data to the user.
It represents the user interface part of the application.
Model handles business logic and domain objects.
Controller handles user actions and connects View with Model.

Formal methods are used to specify, develop and verify software systems.
They use strict and precise notation.
This notation is mainly based on mathematics, logic and set theory.
So, formal methods predominantly use mathematical notation.

An SRS is called unambiguous when every requirement has only one clear meaning.
It means different readers should not interpret the same requirement in different ways.
Correct SRS means requirements match actual user needs.
Consistent SRS means requirements do not conflict with each other.
Verifiable SRS means requirements can be tested or checked.
Here, only one interpretation means unambiguous SRS.

Availability formula is:

$Availability=\frac{MTBF}{MTBF+MTTR}$

Given,

$Availability=99.99\%=0.9999$

$MTBF=1$ day $=24\times60\times60=86400$ seconds

Now,

$0.9999=\frac{86400}{86400+MTTR}$

$86400+MTTR=\frac{86400}{0.9999}$

$MTTR=\frac{86400}{0.9999}-86400$

$MTTR\approx 8.64$ seconds

So, repair time should be approximately $9$ seconds.

In Software Configuration Management, source control should contain files that are needed to build, understand and maintain the software.

Code files should be committed because they are the main source of the software.

Documentation files should also be committed because they describe the system, design, usage and requirements.

Output files are usually generated after execution or build, so they should not normally be committed.

Automatically generated files are also generally not committed unless there is a special requirement.

Therefore, A and B only are correct.

Waterfall model divides the project into fixed stages, so it has inflexible partitioning. Thus, $A-IV$.

Evolutionary model develops software through repeated versions or increments. Thus, $B-I$.

Component-based software engineering uses already available components, so requirement compromises may be needed according to available components. Thus, $C-II$.

Spiral development explicitly focuses on risk analysis in every cycle. Thus, $D-III$.

Final matching is $A-IV,\ B-I,\ C-II,\ D-III$.